I have just installed IntelliJ 9.0.2 on a machine running 64-bit Ubuntu 10.04.
How do I get another window to put on my second screen?
I would like to have both an editor and some tool windows on both screens.
IntelliJ 14 and onwards you can select the settings cog and tick floating mode to detach menus, or drag editor tabs off the main window to detach them
If you're running on OSX you'll need to make sure it's not treating the screens as separate spaces, otherwise they'll snap back onto the same window as the main editor when switching between windows.
To do this untick Displays have separate Spaces in the Mission Control System Preferences.